Reinforcement learning would enjoy better success on real-world problems if domain knowledge could be imparted to the algorithm by the modelers. Most problems have both hidden state and unknown dynamics. Partially observable Markov decision processes (POMDPs) allow for the modeling of both. Unfortunately, they do not provide a natural framework in which to specify knowledge about the domain dyn...

We consider the situation of a homogeneous swarm of agents following a partially observable leader agent. The resulting, slightly heterogeneous swarm of agents is softly controlled by the leader. We study the swarm dynamics using a recently established connection existing between multi-agents dynamics and nonlinear optimal state estimation. For a whole class of nonlinear agents interactions, we...

We investigate a system of partial differential equations modeling ionized magnetized reactive gas mixtures. In this model, transport fluxes are anisotropic linear combinations of fluid macroscopic variable gradients and also include the effect of macroscopic electromagnetic forces. By using entropic variables, we first recast the system of conservation laws into a partially symmetric conservat...

Parametric instabilities driven by partially coherent radiation in plasmas are described by a generalized statistical Wigner-Moyal set of equations, formally equivalent to the full wave equation, coupled to the plasma fluid equations. A generalized dispersion relation for stimulated Raman scattering driven by a partially coherent pump field is derived, revealing a growth rate dependence, with t...

Inadequate nutrition complicates the clinical course of critically ill patients, and many of these patients develop pulmonary edema. However, little is known about the effect of malnutrition on the mechanisms that resolve alveolar edema. Therefore, we studied the mechanisms responsible for the decrease in alveolar fluid clearance in rats exposed to malnutrition. Rats were allowed access to wate...

Fluid-approximation or mean-field techniques are currently very popular approaches to the efficient analysis of massivelyparallel Markov models. In this paper, we exploit the ODE-representation of these approximations to develop efficient techniques for simultaneous partially-symbolic numerical integration over parameter ranges. In particular, we borrow the Taylor model data structure of Makino...

We report that a variety of ternary particle/liquid/liquid mixtures heavily aggregate or separate completely if (1) the particles are fully or almost fully wetted by one fluid, and (2) if the wetting fluid volume fraction is comparable to the particle volume fraction. Aggregation and separation do not happen if the particles are partially wetted by both fluids, in which case Pickering emulsions...

Paraplegia or paraparesis secondary to spinal cord ischemia is an extremely rare complication after elective repair of abdominal aortic aneurysm. We report delayed paraparesis after endovascular abdominal aortic aneurysm repair in which one hypogastric artery was unintentionally occluded due to atheroembolism. A spinal catheter was immediately inserted after onset of paraplegia to promote cereb...

We have developed an efficient algorithm for steady axisymmetrical 2D fluid equations. The algorithm employs multigrid method as well as standard implicit discretization schemes for systems of partial differential equations. Linearity of the multigrid method with respect to the number of grid points allowed us to use 256×256 grid, where we could achieve solutions in several minutes. Time limita...

The short answer to the above question is no, not in general. Although the issues involved remain partially open, the present brief is an attempt to clarify some of the misconceptions and misuses embroiled in the subject of bulk viscosity. Consider the genesis of the query. To close the equations of motion for a continuum fluid, a relation between surface forces and the flow field is needed. A ...